Delivery system for agricultural chemicals

ABSTRACT

An emulsifiable concentrate comprising an agriculturally active chemical, a surfactant, an organic diluent and a solvent having first and second components, the first component being capable of solubilizing the agriculturally active chemical and the second component in conjunction with the surfactant being effective to disperse the agriculturally active chemical. The inventive concentrate allows for high concentrations of the active ingredient, exhibits excellent stability and produces highly stable compositions upon dilution with water.

BACKGROUND OF THE INVENTION

I. Field of the Invention

The invention relates to a delivery system for agriculturally active chemicals. More particularly, the invention relates to an emulsifiable concentrate of difficult to dissolve agricultural chemicals.

II. Descriotion of the Prior Art

Agricultural chemicals are most preferably applied in the form of aqueous emulsions, solutions, or suspensions. Occasionally, they may also be applied in the form of a dust wherein the active ingredient is adsorbed onto or mixed with a finely divided inert carrier material, such as, china clay, or the like. With such powdered or dust compositions, drift due to wind is a problem and consequently, liquid formulations are preferred.

One of the problems with such liquid formulations is the fact that chemicals having agricultural activity often exhibit extreme insolubility in water. This results in their having to be dissolved either in organic solvents or utilized in the form of emulsions or suspensions. With respect to the use of organic solvents, these are generally disadvantageous from an environmental and cost view point. Particularly, such organic chemicals may exhibit toxicity or side-effects which may be adverse to the effect of the agricultural chemical itself or to the subsequent fruit or vegetable produced in the particular agricultural use. This toxicity may also be disadvantageous with respect to handling.

When attempts are made to provide emulsified or suspension formulations, difficulties are encountered with respect to providing a desirably high concentration of the agriculturally active ingredient. Thus, when such agriculturally active chemicals are formulated into an emulsion, it is difficult to maintain the emulsified state. This makes it difficult to maintain a uniform formulation, particularly, when the formulation is diluted with water for application to the plants.

Typically, for example, the agriculturally active ingredient is mixed with one or more of a variety of conventional solvents and an emulsifying agent to form a concentrate. This concentrate may be an emulsion, suspension, or solution. The concentrate is then stored until it is transported to the site of use or may simply be transported and stored at the site of use. In any event, the concentrate normally will undergo some poeriod of storage until it is ready for use. Undertandably, it is most desirable to be able to transport the argiculturally active ingredient at the highest concentration possible so as to minimize the volume of material which need be transported. By the same token, however, at the use site, it is normally not feasible to admix ingredients together or to process them other than to dilute the concentrate with water. Accordingly, it is important that the concentrate emulsify easily, i.e., exhibit good "bloom", upon the addition of water. In addition, at the use site, it is often necessary to store the diluted concentrate for extended time periods until the actual application to the plants. Consequently, it is important that the diluted form of the concentrate exhibit good stability with respect to the uniformity of the emulsion and to avoid precipitation of the active ingredients. If non-uniformity or precipitation occurs in the diluted form, then non-uniformity will result in the application of the diluted formulation to the plants.

An attempt to provide concentrates of agriculturally useful chemicals is disclosed in South African Patent application No. 695,393, filed July 25, 1969. This application is directed to the formulation of a concentrate substantially water-insoluble pesticides for agricultural use. The peticides, either in oil or solid form, are mixed with pyrrolidones having a hydrogen or a lower alkyl group containing from 1 to 4 carbon atoms attached to the nitrogen atom of the pyrrolidne ring. The application discloses that concentratied solutions of difficult to dissolve perticides could be formulated and that such concentrates exhbiited good stability. The concentrates utilized are those containing the pesticidal active ingredient, the particular lower alkyl pyrrolidone, a co-solvent which is usually a common organic solvent, such as, an aromatic including xylene, methylated and polyalkylated naphthalenes and aliphatic solvents, and a dispersing or emulsifying agent, such as, a surfactant, including polyoxyethylene alkylphenols, polyoxyethylene fatty esters, polyoxyethylene sorbitan fatty esters which may be blended with oil-soluble sulfonates, calcium and amino-sulfonate salts, and the like.

This prior art does not offer a solution to the problem arising from the difficulty in maintaining the stability of the emulsion after the concentrate is diluted with water. Consequently, unless the diluted form of the concentrate is used immediately after emulsification, it is difficult to provide a stable diluted formulation for application to the plants.

U.S. Pat.No. 4,798,837 discolses an emulsifiable concentrate of the pesticidal compound (CGA): ##STR1##

This active concentrate contains 10% of the active ingredient using 30% cyclohexanone as the solvent. However, cyclohexanone is highly toxic. For such agricultural uses, it is desirable to avoid the use of toxic solvents, including those of Lists 1 and 2 of 40 C.F.R. 154.7 dated Apr. 22, 1987, which includes inerts of toxicological concern and solvents having high flash points, as well as to increase the amount of the agriculturally active material in the concentrate.

SUMMARY OF THE INVENTION

We have discovered a novel emulsifiable concentrate of an agriculturally active chemical, which concentrate provides, upon dilution, a highly stable emulsion. In addition, the inventive emulsifiable concentrates may contain relatively high concentrations of th agriculturally active ingredient making it advantageous from both economic and handling viewpoints. Also, the concentrates of the present invention utilize organic materials which do not pose environmental problems either in use or handling.

More particularly, the emulsifiable concentrate of the present invention is composed of an agriculturally active chemical, a surfactant, an organic diluent, and a solvent having a first component and a second component.

The first component of the solvent is selected from those compounds which have a sufficiently high hydrophilic property to solubilize the agriculturally active chemical. Preferably, the first component will have the following Hansens' solvent parameters:

Dispersable component from about 40 to 50%; Polar components of from about 25 to 40%; and H-bonding components of 10 to 30%.

The second component is a hydrophobic solvent having the following Hansens+ solubility parameters:

Dispersive component from about 56 to 75%; Polar component from about 8 to 24%; and H-bonding component of from about 10 to 30%.

This second component should also have surfactant properties and act as a non-ionic surfactant with an HLB value ranging from about to 2 to 8.

For a discussion of the solubility parameters, see C.R.C. Handbook of Solubility Parameters and Other Cohesion Parameters, Allan F.M. Barton, 1983, Table 9, p. 167-170.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As used herein, the term "agriculturally active chemical" includes compounds and mixtures thereof which can be used as agricultural fertilizers, nutrients, plant growth accelerants, herbicides, plant growth controlling chemicals, and chemicals which are effective in killing plants, insects, microorganisms, fungi, bacteria and the like which are commonly referred to as insecticides, bactericides, fungicides, nematocides, fumigants, and the like, as well as any other chemicals having properties which are suitable for agricultural uses in terms of application to plants or domestic uses for controlling insects and pests. Particularly, such chemicals would normally take the form of water-immiscible or oily liquids and/or solids which is substantially insoluble in water. By the term "substantially insoluble", it is meant that for all practical purposes, the solubility of the compound in water is insufficient to make the compound practicably usable in an agricultural end use without some modification either to increase its solubility or dispersability in water, so as to increase the compound's bioavailability or avoid the use of excessively large volumes of solvent.

Suitable agriculturally active chemicals which can be used with the present invention include insecticides, such as, cyclocompounds, carbamates, animal and plant derivatives, synthetic pyrethroids, diphenyl compounds, non-phosphates, organic phosphates, thiophosphates, and dithiophosphates. (See Argicultural Chemicals, Book I, Insecticides, 1989 Revision by W. T. Thomson, Thomson Publications.) Typical of the insecticides are:

cyclocompounds:

6,7,8,9,10,10,-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide

carbamates:

2-isopropyl phenyl-N-methyl carbamate;

2-(1,3-dioxolan-2-yl) phenylmethyl carbamate; 2,3-isopropylidine dioxyphenyl methyl carbamate;

animal and plant derivatives:

chlorinated hydrocarbons derived from Southern pine; naturally occuring lactone glycoside;

synthetic pyrethroids:

(±) α-cyano-3-phenoxybenzyl (±) dis, trans 3-(2,2-dichlorovinyl)-2,2-di-methyl cyclopropane carboxylate;

(±) cyano (3-phenoxyphenyl methyl (±)-4-(difluoromethyoxy) α-(1-methylethyl) benzene acetate;

phenoxy compounds and non-phosphate:

2,2-bis (p-methoxy phenyl)-1,1,1,tri-chloroethane;

1,3,5tri-n-propyl-1,3,5-triazine-2,4,6

(1H, 3H, 5H) trione; ethyl (2E, 4E)-3,7,11-trimethyl-2,4-dodeca dienoate;

1-decycloxy 4-[(7-oxa-oct-4-ynyl)]-oxybenzene;

organic phosphates:

dimethyl phophate ester of 3-hydroxy-N,N-dimethyl-cis-crotonamide; 2-chloro-1-(2,4-dichloro phenyl) vinyl diethylphosphate;

4-(methyl thio) phenyl dipropyl phosphate;

thiophosphates:

0,0-diethyl-0-4-nitrophenyl phosphorothioate;

0,0-diethyl-0-(2-isopropyl-6-methyl-5-pyrimidinyl) phosphorothioate;

2-diethylamino-6-methyl pyrimidine-4-yl dimethyl phosphorthioate;

dithiophosphates:

0,0-dimethyl phosphorodithioate ester of diethylmercapto succinate;

0-ethyl-S-phenyl ethyl phosphorodithioate.

Typical herbicides include phenoxy compounds, benzoic, acetic, and phthalic acids, aniline derivaties, niriles, amides, acetamides, anilides, carbamates, thiocarbamates, and heterocyclic nitrogen derivaties, e.g., triazines, pyridines, pyridazones, picolinic acid, and urea derivates and phosphates. (See Aoricultural Chemicals. Book II, Herbicides, 1986-87 Edition, W. T. Thomson, Thomson Publications, Fresno, CA 93791.) Exemplary of the above compounds are:

phenoxy compounds:

2,4-Dichlorophenoxy acetic acid 2,4,5-trichloro phenoxyacetic acid; 4-(2,4-dichlorophenoxy) butyric aicd;

S-ethyl 2 methyl-4-chlorophenoxy-thioacetate;

2-methyl-4-chloro-phenoxy acetic acid;

methyl 5-(2,4-dichloro-phenoxy)-2-nitrobenzoate;

benzoic and acetic acids of phthalic compounds:

3,6-dichloro-o-anisic acid

4-chloro-2-oxo benzothiazolin-3-yl acetic acid;

N-1-Naphthyl-pthalamic acid;

nitriles and aniline derivatives:

3-5-dibromo-4-hydroxybenzo-nitrile; α,α,α,trifluoro-2,6-dinitro-N, N-dipropyl-p-tolinidine;

N-(1-ethylpropyl)-2,6-dinitro-3,4-xylidine;

amides, acetamides, anilides:

N,N-diethyl-2-(1-naphthalenyl oxy)-propionamide;

2,6-dimethyl-N-2'methoxy-ethyl-chloro-acetanilide;

3',4'-dichloro-propionanilide;

α-chloracetic-N-(3,5,5-trimethyl-cyclohexen-1-yl)-N-isopropylamide;

4-benzyl-N-isopropyl trimethyl acetamide;

thiocarbamates:

S-Ethyl dipropyl thiocarbamate;

urea derivatives:

3-(5-tert-butyl-3-isoxazoyl)-1,1dimethyl urea;

N-(2,6-trifluoro-benzoyl)-N'-[2,5-dichloro-4-(1,1,2,3,3,3-hexafluoro-propyloxy) phenyl]urea;

pyrrolidone derivatives:

1-(m-trifluoro methyl phenyl)-3-chloro-4-chloromethyl-2-pyrrolidone;

amino acid derivatives:

Methyl-N-benzoyl-N-(3-chloro-4 fluorophenyl)-DL alarinate; N-chloroacetyl-N-(2,6-diethyl phenyl)-glycine ethyl ester;

carbamates:

Isopropyl-m-chlorocarbanilate; 3-Ethoxy (carbonyl aminophenyl)-N-phenyl carbamate;

heterocyclics:

4-amino-3,5-dichloro-6-fluoro-2-pyridyloxy acetic acid;

4-(1,2-Dimethyl-N-propyl amino)-2-ethyl amino-6-methyl thio-S-riazine;

2-[4,5-dihydro 4-methyl-4-(1-methyl ethyl)-5-oxo-1 H-imidazoyl-2yl-3-byridinecarboxylic acid;

2-[3,5-dichlorophenyl)-2-2,2,2-trichloroethyl) oxiane; Butyl-9-hydro-fluoroene-(9)-carboxylate;

2-[1-(ethoxy imino) butyl]-3-hydroxy-5-(2H-tetra hydro thiopyran-3)-2-cyclohexene-ione;

2-(2 chlorophenyl) methyl-4,4-dimethyl-3-iso oxazolidinone;

phosphates:

0-ethyl-0-(3-methyl-6-nitro phenyl) N-sec-butyl phosphoro thio amidate.

Typical fungicides include (See Agricultural Chemicals, Book IV, Fungicides, 1989 Revision, W. T. Thomson, Thomson Publications, Fresno, CA 93791):

organic compounds:

2,5-dimethyl-N-Cyclohexyl-N-methoxy-3-furan carboxamide;

5-Ethyoxy-3-trichloromethyl-l,2,4-thiadiazole;

3-(2-methyl piperidino) propyl dichlorobenzoate;

N,N'-(1,4-piperazinediyl bis (2,2,2-trichloro) ethylidene) bis formamide;

Tetramethyl thiuram disulfide; 0-Ethyl-S,S,diphenyl-dithiophos-phate;

5,10-dihydro-5,10-dioxo naptho (2,3,9)-p-dithiin-2,3-dicarbo-nitrile;

2-(thiocyano methyl thio) benzothia-zole;

α-2-(4-chlorophenyl) ethyl]-α-(1,1-dimethyl ethyl)-1 H-1,2,4-triazole-1-ethanol;

morpholines:

N-tridecyl-2,6-dimethyl morpholine;

4-N-dodecyl-2,6-dimethyl moropholine;

Typical fumigants, growth regulators, repellants, and rodenticides include (See Agricultural Chemicals, Book III, 1988-1989 Revision, W. T. Thomson, Thomson Publications, Fresno, CA 93791):

growth regulants: 1,2 Dihydro-6-ethoxy-2,2,4-tri-methylquinoline;

(2-chloroethyl) phosphoric acid; 4-[acetamino) methyl]-2-chloro-N (2,6-diethyl phenyl acetamide;

Benzoic acid, 3,6 dichloro-2- methoxy,2-ethoxy-1-methyl-2-oxo ethyl ester;

repellants:

0,0-dimethyl-0-[(4-m-tolyl] phosphorothioate;

Tetriary butyl-sulfenyl dimethyl dithio carbamate;

seed softener:

2-chloro-6-(trichlomethyl) pyridine; 5-ethoxy-3-trichloromethyl-1,2,4-thiadiazole;

N-phenyl-N'-1,2,3-thiadiazol-5-yl urea;

Pesticides may be characterized by their physical properties depending on their physical state at normal or ambient conditions, i.e., between 40° F. and 90° F. and their solubility or miscibility with water or other common organic solvents, e.g., aromatics, such as, toluene, xylene, methylated and polyalkylated naphthalenes, and aliphatic solvents.

Based on the physical properties, the pesticides may be classified into two groups. The first group includes those which are oily liquids at ambient temperatures and are immiscible with water. Specific pesticides include:

Common esters of 2,4-dichlorophenoxyacetic acid,

Common esters of 2,4,5-trichloro-phenoxyacetic acid,

Common esters of 2-(2,4-dichlorophenoxy) propionic acid,

Common esters of 2-(2,4,5-trichlorophenozy) propionic acid,

Common esters of 2,4-dichlorobutyric acid,

Common esters of 2,methoxy-3,6-dichlorobenzoic acid,

Common esters of 2-methyl-4-chlorophenoxyacetic acid,

Piperonyl butoxide 3,4-methylenedioxy-6-propyl benzyl n-butyl diethylene glycol ether,

Bromophos ethyl: 0,0-diethyl-0-2,5-dichloro-4-bromophenyl thionophosphate,

N-(2-mercaptoethyl) benzene-sulfenamide (BETASAN®),

Isobornyl Thiocyanoacetate (Thanite®),

Ioxynil ester of octanoic acid,

Molinate S-ethyl hexahydro - 1 H - azepine-1-carbothioate,

PP 5111 0,0-dimethyl-(2-diethylamine 4-methyl-6-pyrimidinyl) carbamate,

PP 211 0,0-diethyl 0-(2-diethylamine-4-methyl-6-pyrimidinyl) phosphorocarbamate,

Chlordane

5-Ethoxy-3-(trichlorometyl)-1,2,4-thiadiazole (TERRAZALE®), Ethyl-s-s-dipropyl-phosphodithioate (MOCAP®),

S-Ethyl dipropylthiocarbamate (EPTAM®),

S-Ethyl diisobutylthiocarbamate (SUTAN®),

S-n. propyl-di-n-propylthiocarbamate (VERNAM®),

S-propyl butylethylthiocarbamatae (TILLAM®),

S-ethyl ethylcyclohexylthiocarbamat (RO-NEET®),

Malathion (S-(1,2-dicarboxyethyl)-0,0-dimethyl phosphorodi-thioate),

Diazinon (0,0-diethy1,0-(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate,

0-Ethyl-S-phenyl-ethylphosphonodithioate Toxaphene (Octachlorocamphene),

Bromoxynil (3,5-dibromo-4-hydroxy benzonitrile ester of n.octanoic acid,

2-chloro-N-2,6-diethylphenyl-N-methoxymethylacetamide (LASSO®),

Diallate S-2,3-dichloroallyl N,N-diisopropylthiolcarbamate,

Triallate S-2,33-trichloroallyl N,N-diisopropylthiol-carbamate.

The second group comprises those pesticides which are solids at ambient temperatures and for all practical purposes, insoluble in water.

2,4,5-T (2,4,5-trichlorophenoxy acetic acid)

1,1-dimethyl urea)

Monuron (3-(p-chlorophenyl)--1,1-dimethyl urea)

Diuron (3-(3,4-dichlorophenyl)-1,1-dimethyl urea)

Bromacil (5 bromo-3-sec. butyl-6-methyl uracil)

Isocil (5 bromo-3-isopropyl-6-methyl uracil)

Linuron (3-(3,4 dichlorophenyl)-1-methoxy-1 methyl urea

Atrazine (2-chloro-4-ethylamino-6 isopropylamino-s-trriazine)

Simazine (2-chloro-4,6,-bis (ethylamino)-s-triazine

Dodine (n-dodecylguanidine acetate)

Thiram (tetramethylthiuram disulfide)

N-(mercaptomethyl)phthalimide s-(o,o dimethylphosphoro-dithioate) (IMIDAN®)

Lindane (gamma 1,2,3,4,5,6 hexachlorocyclohexane)

Folpet (N-trichloromethylphthalimide)

Manazon (s-(4,6-diamino-1,3,5-triazin-2-yl methyl)dimethyl

phosphorothiolthionate)

Barban (4-chloro-2 butynyl m-chlorocarbanilate)

Tricumba 2-methoxy-3,5,6-trichlorobenzoic acid

Trifluralin (2,6-dinitro-N,N-dipropyl-4-trifluoro-methylamiline) (2,3 dihydro-5-carboxanilido-6-methyl-I,4-oxathiin) (VITAVAX®)

2,4-dichlorophenoxyacetic acid

4-(4-chloro-2 methylphenoxy) butyric acid

2-(2,4-dichlorophenoxy) propionic acid

Ioxynil: 3,5 diiodo-4-hydroxybenzonitrile Bromoxynil: 3,5 dibromo-4-hydroxybenzonitirle

Carbaryl: 1-naphthyl-N-methylcarbamate

Methoxychlor: 2,2,-Bis(p-methoxyphenyl)-1,1-trichloroethane

PP 781: 4(2-chloro phenylhydrazono)-3-methyl-5-isoxazolone*

PP 675: 5-butyl-2-dimethylamino-4-hydroxy-6-methyl pyrimidine*

PP 062: 5,6-dimethyl-2-dimethylamino-4 pyrimidinyl dimethylcarbamate*

PP 149: 5-n-butyl-2 ethylamino-4-hydroxy-6 methylpyrimidine*

* Manufactured by Imperial Chemical Industries Limited

C 6313 N'-(4-bromo-3-chlorophenyl)-N-methoxy-N-methylurea

C 6989 2,4'dinitro-4-trifluoromethyl-diphenylether

Chloroxuron N'-4-(chlorophenoxy) phenyl-NN-dimethylurea

Dichlobenil 2,6-dichlorobenzonitrile

Diphenamid NN-dimethyl-2,2-diphenylacetamide

Fenac 2,3,6-trichlorophenylacetic acid

Fluometuron N'-(3-trifluoromethylphenyl)-NN-dimethylurea

GS 14260 4-ethylamino-2-methylthio-6-t-butyl-amino-1,3,5-triazine

PCP Pentachlorophenol

Lenacil 3-cyclohexyl-6,7-dihydro-lH-cyclo-pentapyrimidine-2,4-(3H,5H)-dione

Pyrazon 5-amino-4-chloro-2-phenyl-3-pyridazone

Metrobromuron N'-(4-bromophenyl)-N-methoxy-N-methylurea

Metoxymarc N-(4-methoxybenzoyl)-N-(3,4-dichlorophenyl)-N',N'-dimethylurea

Neburon N-butyl-N'-(3,4-dichlorophenyl-N-methylurea

NIA 11092 1,1-dimethyl-3-[3-(n-t-butyl carbamyloxy)phenyl]urea

Mecoprop 2-(4-chloro-2 methylphenoxy)propionic acid

Nitrofen 2,4-dichlorphenyl 4-nitrophenylether

Propanil N-(3,4-dichlororphenyl)propionamide

Pyriclor 2,3,5-trichloro-4-pyridinol

Solan 3'-chloro-2-methyl-p-volerotoluidide

Terbacil 5-chloro-3-t-butyl-6-methyluracil

UC 22463 (SIRMATE)-3,4-dichlorobenzyl N-methylcarbamate

WL 9385 2-Azido-4-ethylamino-6-t-butylamino-s-triazine

Propachlor 2-chloro-N-isopropylacetanilide

CP 50144 2-chloro-N-2,6-diethylphenyl-N-methoxymethylacetamide

CP 31675 2-chloro-N-(2 methyl-6-t-butylphenyl)acetamide

Cypromid 3',4'-dichlorocyclopropane carboxanilide

Fenuron NN-dimethyl-N'phenylurea

Chlorbromuron N'-(4-bromo-3-chlorophenyl)-N-methoxy-N-methyl-urea

Ametryen 2-methylmercapto-4-ethylamino-6-isopropyl-amino-s-triazine

Prometryne 2-methylmercapto-4,6-bisisopropyl amino

DCPA dimethyl 2,3,5,6, tetrachloroterephthalate

Benefin N-butyl-N-ethyl-2,2,2-trifluoro-2,6-dinitro-p-toluidine

Nitralin 2,6-dinitro-4-methylsulfonyl-NN-dipropyl-aniline

PP 493 2,6-difluoro-3,5-dichloro-4-hydroxy pyridine

CNP 2,4,6-trichlorophenyl-4'-nitrophenyl ether

Pentachloro nitrobenzine

1-(butile carbamoy)-2-benzimidazol carbamic acid, methyl ester (BENLATE®)

Typical examples of first components suitable for use in the solvent are alkylpyrrolidones having from 1 to 4 carbon atoms in the alkyl group, cyclic lactones, e.g., gamma-butyrolactone, lower alkyl cyclic carbonates, i.e., ethylene carbonate, propylene carbonate, butylene carbonate, lower akylimidazolone, e.g., N-N,dimethylimidazolone, lower alkylamides of formic acid and acetic acid, e.g., dimethyl formamide and dimethylacetamide, and lower alkyl sulfoxides, e.g., dimethylsulfoxide. (The term "lower alkyl" in these examples means one or two carbons.) Mixtures of these may also be used as the first component.

Examples of appropriate second components include alkylpyrrolidones having an alkyl portion containing from 6 to 14 carbon atoms, e.g., octylpyrrolodone, dodecylpyrroli-done, or N-(2'-ethylhexylpyrrolidone), alkyl gamma-butyrolac-tones, alkyl cyclic carbonates and combinations thereof, wherein the alkyl chains contain from 6 to 14 carbon atoms. The alkyl portion may be distributed at one or more sites on the ring so long as one portion contains at least 6 carbon atoms and the total number of alkyl carbon atoms does not exceed 14. For each of the above examples, the 6 to 14 carbon alkyl portions may be straight or branched.

Preferably, the first component is selected from the group consisting of pyrrolidones having the formula ##STR2## wherein R is hydrogen or lower alkyl having from 1 to 4 carbon atoms and R is lower alkyl having from 1 to 4 carbon atoms.

The second component is preferably selected from pyrrolidones having the formula ##STR3## wherein R₂ is hydrogen or alkyl having from 6 to 14 carbon atoms and R₃ is alkyl having from 6 to 14 carbon atoms with the proviso that at least one of R₂ or R₃ must contain at least 6 carbon atoms and the sum of the carbon atoms in R₂ and R₃ cannot exceed 14.

The inventive composition further comprises an organic diluent which is a synthetic or naturally occurring oils having a high hydrophobic character or having a fractional dispersive solubility parameter of greater than 70% and preferably greater than 85% and a molar volume of greater than 90 cm³ /mole. These properties are defined in the C. R. C. Handbook referred to hereinabove. Typical diluents include soybean oil, rapeseed oil, long chain alcohols, long chain ketones, long chain esters, and ethers. As used herein, "long chain" means with 6 or more carbon atoms. Also suitable as the organic diluent are aromatic petroleum oils including those which are commercially available distillates from crude oils having an average boiling point greater than 200° C. Typical of such materials are those sold under the trademarks Exxon 200 or Texaco 400. Of course, such aroma-tics should be approved for use as a carrier for agriculturally active chemicals.

The composition of the aromatic petroleum oil is generally:

Heavy aromatic solvent naphtha--about 60%;

Middle distillate solvent extractant--about 40%.

Normally, these oils contain predominantly the C₉ -C₁₅ aromatic hydrocarbons and primarily the C₁₀ -C₁₂ hydrocarbons having a flash point of about 203° F.

In the inventive composition, the amount of solvent is in the range from about 20 to 90%, and the amount of diluent is about 80 to 10%, based on the weight of solvent and diluent in the composition. With respect to the solvent, the amount of the first component is from about 5 to 95% and preferably, 20 to 80%; and the amount of the second component is from about 5 to 95%, and preferably, 20 to 80%, based on the weight of the solvent.

The inventive composition also contains one or more additional emulsifier or surfactant which is generally selected on a case by case basis in order to optimize the solubility and stability of the emulsion. Typically, such emulsifiers include ethoxylated alkyl phenols, linear aliphatic polyesters, linear aromatic polyesters, polyethoxylated alcohols, linear aliphatic ethoxylates, polyethoxylated castor oil, polyethoxylated carboxylates, and polyethoxylated alkylamines. Anionic surfactants may be used as the emulsifier and include phosphate esters and their salts, alkyl sulfonamides, salts of sulfated nonylphenoxypoly(ethyleneoxy) ethanol, salts of alkylbenzene sulfonates, salts of alkylnaphthalene sulfonate, and sulfonated aliphatic polyesters and their salts. Also suitable are complex phosphate esters of nonionic surfactants of the ethylene oxide type which are mixtures of diesters of phosphoric acid. (See, for example, McCutcheon's, Emulsifiers and Deteroents (1989), published by McCutcheon's Division of M.C. Publishing Co., Glen Rock, New Jersey.) Generally, the amount of emulsifier (surfactant) is from about 1 to 25% based on the total weight of the composition.

The agriculturally active chemical (sometimes referred to herein as AAC) concentration should be as high as possible so long as it does not precipitate out upon dilution of the concentrate with water for a reasonable period of time and achieves the desired effect. With the present invention, it is possible to obtain concentrates with agriculturally active chemical concentrations in excess of 5 weight percent which form a stable emulsion upon being diluted with water. Depending on the particular agriculturally active chemical, the concentration of the AAC is from about 5 to 60% based on the total weight of the composition before dilution.

The following examples illustrate the present invention*: * In the examples, all compositional percentages are percent by weight of the total composition unless otherwise indicated.

EXAMPLE 1

A series of twelve compositions wherein the amount of a first pyrrolidone component (N-methylpyrrolidone), second pyrrolidone component (N-octylpyrrolidone) and aromatic solvent were varied using a surface-active agent from 14.3% to 22.2% by weight and agriculturally active chemical from 25.8% to 41.6% by weight. (See Table 1.) The surface-active agent was Gafac RE-610 (ethoxylated phosphate ester), and the agriculturally active chemical (AAC) was N-(1-ethylpropy)-2,6-dinitro-3,4-xylidine (PRL).

Formulations:

Formulations were made by mixing together the components comprising of each composition by weigh.rng the exact proportion of ingredients in a bottle. The solvents were weighed in first. The AAC was dissolved completely in the solvent system followed by addition of the wetting agent or emulsifying agent. Typically, about 20g of each of the formulations was prepared. As an illustration, formulation #11 included in Table 1-2 was prepared by weighing together the following ingredients in a one ounce bottle:

                  TABLE 1-1                                                        ______________________________________                                         N-methylpyrrolidone                                                                               2.75 g   20.4%                                              N-octylpyrrolidone 1.25 g    9.3%                                              Aromatic Petroleum oil                                                                            1.00 g    7.4%                                              Exxon 200                                                                      PRL                5.50 g   40.7%                                              (N-1 ethyl propyl)-2,6-                                                        dinitro-3,4-xylidine                                                           (92% Tech.)                                                                    Phosphate ester    3.00 g   22.2%                                              (Gafac RE-610)                                                                 TOTAL:             13.50 g  100.0%                                             ______________________________________                                    

The contents were stirred well in an automatic rocking shaker for about 30 minutes when the AAC dissolved completely. The samples thus prepared were evaluated for freeze-thaw stability on storage and ease of emulsification and emulsion stability on dilution.

Freeze-Thaw Stability:

The concentrates were stored for a period of 24 hours in the cold temperature 5° C.) in a refrigerator and taken out and thawed to room temperature and then stored at 55° C. in an oven for a period of 24 hours. The alternate storage in the cold (5° C.) and warm condition at 55° C. was repeated for three cycles. Any separation during the storage was recorded. A concentrate is "stable" if there is no substantial separation after the 24 hour cycles at each temperature.

Evaluation of Emulsion Stability and Ease of Emulsification:

A Nessler tube (1.8 cm diameter; 28 cm long) was filled with appropriate quantity (47-48 g) of World Health Organization (WHO) standard (6g of CaCl₂ and 2.87 g of MgCl₂ 6H₂ O dissolved in 20L) hard water having a hardness of 342 ppm expressed as Na equivalent, Using a serological pipette, 0.5-2.5 g of emulsion concentrate was dropped into the Nessler tube containing 47.5-49.5 water. The initial bloom was observed at zero time without stirring and the quality of the bloom was graded by visual appearance as shown below. The Nessler tube was stopped and inverted 20 times; the bloom was again recorded and so also stability as judged by volume or height of the sedimentation (cream/ppt/oil) followed at different internvals of time: 0, 1 hours, 2 hours, up to 24 hours.

Stability of Diluted Concentrate:

The composition of the cencentrate (EC) diluted with water was considered "stable" if at EC concentrtions of from 0.2 to 1%, the composition after mixing (twenty inversions) exhibited two mm or less cream and no oil in one hour. Both top and bottom should be checked.

Bloom

Excellent--Thick emulsion cloud with no separation

Good--Emulsion cloud may be thin, or may exhibit trailing, small number of oil droples within cloud

Poor--Many oil droplets within cloud, some droplets separate from cloud

Each of the emulsifiable concentrates thus prepared were analyzed for ease of emulsification (bloom) upon addition of water and after twenty inversion of the sample as well as emulsion stability upon dilution with water. The composition of the samples are set forth in Table 1-2 and the results of the analysis are set forth in Table 1-3. The freeze-thaw stability was measured as follows: Compositions 1 through 7 included in Table 1-2 passed freeze-thaw stability test when stored at -10° C. to 55° C. for 3 cycles of 24 hour periods. Composition 8 through 12 included in Table 1-2 passed freeze-thaw stability test when stored at 5 C. to 55° C. for 3 cycles of 24 hour periods. Formulations 11 showed maximum freeze-thaw stability with PRL at 40.7%.

                                      TABLE 1-2                                    __________________________________________________________________________     Ingredient 1   2   3    4   5   6    7   8   9    10  11   12                  __________________________________________________________________________     N-methylpyrrolidone                                                                       30.0                                                                               33.0                                                                               0    30.0                                                                               24.0                                                                               60.0 0   18.2                                                                               22.2 29.7                                                                               20.4 14.8                (M-Pyrol)                                                                      N-octylpyrrolidone                                                                        30.0                                                                               15.0                                                                               0    0   18.0                                                                               0    60.0                                                                                7.3                                                                                6.7  3.7                                                                                9.3 11.0                (LP-100)                                                                       Aromatic oil                                                                              0   12.0                                                                               60.0 30.0                                                                               18.0                                                                               0    0   11.0                                                                                8.2  3.7                                                                                7.4 11.0                (Exxon 200)                                                                    Gafac RE-610                                                                              14.3                                                                               14.3                                                                               14.3 14.3                                                                               14.3                                                                               14.3 14.3                                                                               21.9                                                                               22.2 22.2                                                                               22.0 22.0                PRL, 92% Tech.                                                                            25.9                                                                               25.9                                                                               25.8 25.8                                                                               25.8                                                                               25.8 25.8                                                                               41.6                                                                               40.7 40.7                                                                               40.7 41.2                Solvent ratio                                                                  M-pyrol    50  55  0    50  40  100  0   50  60   80  55   40                  LP-100     50  25  0    0   30  0    100 20  18   10  25   30                  Ar. Exxon 200                                                                             0   20  100  50  30  0    0   30  22   10  20   30                  Water used for                                                                            WHO WHO WHO  WHO WHO WHO  WHO WHO WHO  WHO WHO  WHO                 dilution   342 342 342  342 342 342  342 342 342  342 342  342                 hardness ppm                                                                   Concentration                                                                              0.65                                                                               0.65                                                                               0.65                                                                                0.65                                                                               0.65                                                                               0.65                                                                                0.65                                                                               0.83                                                                               0.83                                                                                0.83                                                                               0.83                                                                                0.83               of AAC (% in                                                                   diluted sample)                                                                __________________________________________________________________________

                                      TABLE 1-3                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                                    Stability                                                                      Thickness of                                                                   Separation                                                                            Separation after                                       Bloom            cream, oil or                                                                         Mixing and standing for:                               Bloom at  After 20                                                                              precipitation                                                                         1    2    24                                           Zero Time*                                                                               Inversions**                                                                          at 0 time                                                                             hours                                                  __________________________________________________________________________     1  poor-fair                                                                             excellent                                                                             20 mm  <1 mm                                                                               <1 mm                                                                               crystals                                                      cream ppt        to the top                                   2  excellent                                                                             excellent                                                                             0      0    0    0                                               spont.                                                                      3  excellent                                                                             excellent                                                                             2 mm creamy                                                                           2 mm 2 mm 2.5 mm                                       4  excellent                                                                             excellent                                                                             <1 mm  <1 mm                                                                               1 mm 1 mm                                         5  excellent                                                                             excellent                                                                             0      0    0    0                                               spont.                                                                      6  excellent                                                                             excellent                                                                             0      0    0    <1 mm                                        7  poor   excellent                                                                             1 mm   <1 mm                                                                               1 mm 4 mm cream                                                                     on bottom                                                                      4 mm                                                                           oil on top                                   8  excellent                                                                             excellent                                                                             <1 mm  trace                                                                               trace                                                                               trace                                           spont.                                                                      9  excellent                                                                             excellent                                                                             0      0    0    trace                                           spont.                                                                      10 excellent                                                                             excellent                                                                             trace  0    0    <1 mm                                           spont.                                                                      11 excellent                                                                             excellent                                                                             trace  0    0    trace                                           spont.                                                                      12 excellent                                                                             excellent                                                                             <1 mm  trace                                                                               trace                                                                               trace                                           spont.                                                                      __________________________________________________________________________      *The descriptions have the following meanings:                                 poor-fair  emulsion produced between one and five minutes                      excellent  emulsion produced after two seconds                                 spontaneous  emulsion produced instantly                                       **excellent  complete emulsification obtained. Thick emulsion cloud with       no separation.                                                                 **good  emulsion cloud may be thin, or may exhibit trailing, small number      of oil droplets within cloud                                                   **poor  many oil droplets within cloud, some droplets separate from cloud

EXAMPLE 2

A second series of two experiments was carried out using the following formulation:

                  TABLE 2-1                                                        ______________________________________                                         1.         CGA (98% Tech.)                                                                               22.2%                                                2.         N-methylpyrrolidone                                                                           33.3%                                                3.         N-octylpyrrolidone                                                                            16.7%                                                4.         Texaco Aromatic 400                                                                           16.7%                                                5.         Gafac RE-610 (GAF)                                                                            11.1%                                                                          100.0%                                               ______________________________________                                    

This composition was prepared by weighing out the individual quantities of the ingredients and adding the anionic emulsifier (5) to the N-methylpyrrolidone, admixing the agriculturally active chemical to this mixture, adding the N-octylpyrrolidone to the resulting mixture, and finally, adding the aromatic diluent (4) and mixing the entire composition tomake it uniform. The formulatio thus prepared was clear. Samples of the formulation were stored at -10° C. and 55° C. for each of theee 24 hr. periods. No precipitation nor separation of any of the ingredients was observed for the samples.

The concentrate thus prepared was diluted in a standard 37 cm×2 cm Nessler's tube using WHO standard water. Two dilutions of emulsifiable concentrate to water of 5:100 and 0.6:100 were prepared. The bloom characteristics and emulsion stabilities of each of these dilutions are set forth in Table 3.

                  TABLE 2-2                                                        ______________________________________                                         EMULSION STABILITY AND                                                         BLOOM CHARACTERISTICS                                                          Formulation    I.           II.                                                ______________________________________                                         Conc. of active                                                                               22%          22%                                                Dilution:      2.5:47.5     0.3:49.8                                                          (1/20)       (1/167)                                            Water used for dilution                                                                       WHO standard WHO standard                                                      342 ppm      342 ppm                                            Con. of active in the                                                                         1.11%        0.13%                                              diluted sample                                                                 Bloom at 0 time                                                                               spontaneous  spontaneous                                        After 20 inversions                                                                           excellent    excellent                                          Separation or Precipitation                                                    after mixing and standing for:                                                  1 hour        none         none                                                2 hours       none         none                                                4 hours       none         none                                               10 hours       none         none                                               24 hours       none         none                                               ______________________________________                                    

EXAMPLE 3

A third series of expierments were carried out using the following compositions:

                  TABLE 3-1                                                        ______________________________________                                                             3.I    3.II                                                ______________________________________                                         1.     CGA                20.4%    10.3%                                              (98% Tech)                                                              2.     N-methylpyrrolidone                                                                               34.2%    38.5%                                       3.     N-octylpyrrolidone 17.0%    19.2%                                       4.     Soybean oil        17.0%    19.2%                                              (White Rose polyunsaturated                                                    vegetable oil)                                                          5.     Gafac RE-610 (GAF) 11.4%    12.8%                                                                 100.0%   100.0%                                      ______________________________________                                    

The compositions were prepared by weighing out individual ingredients 1 through 4 and dissolving the anionic emulsifier (5) in the admixture. The entire composition was mixed in an automatic rocking shaker to obtain a uniform and clear composition. Samples of the formulations I and II were stored at -10° C. and 55° C. for each of three 24 hour periods. No separation or precipitation of any ingredients was observed in the two samples. The concentrates thus obtained were each diluted in a standard diluents. In one case, the diluent was deionized water and in the other case, acetic acid at pH 2.5. Two dilutions of emulsifiable concentrate to diluent at 1:20 and 1:66 were prepared for each diluent. The bloom characteristics and emulsion stabilities of each of these dilutions are set forth in Table 4.

                                      TABLE 3-2                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                   Formulation                                                                           I      II     III    IV     V      VI     VII    VIII                   __________________________________________________________________________     Emulsifiable                                                                          3.I    3.I    3.II   3.II   3.I    3.I    3.II   3.II                   concentrate                                                                    used                                                                           conc. of AAC                                                                          20.4%  20.4%  10.3%  10.3%  20.4%  20.4%  10.3%  10.3%                  water used                                                                            deionized                                                                             deionized                                                                             deionized                                                                             deionized                                                                             acetic acid                                                                           at pH 2.5                            for dilution                                                                          water  water  water  water                                              dilution                                                                              2.5/50 0.3/50 2.5/50 0.3/50 2.5/50 0.3/50 2.5/50 10.3/50                factor                                                                         conc. in the                                                                          1.02%  0.12%  1.02%  0.12%  1.02%  0.12%  1.02%  0.12%                  diluted sam-                                                                   ple                                                                            Bloom before                                                                          spontaneous                                                                           spontaneous                                                                           spontaneous                                                                           spontaneous                                                                           spontaneous                                                                           spontaneous                                                                           spontaneous                                                                           spontaneous            mixing Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent              after 20                                                                              Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent                                                                             Excellent              inversions                                                                     separation after mixing and standing for:                                      30 min.                                                                               *      *      *      *      yes, <1 mm                                                                            none   none   none                    1 hour                                                                               none   none   none   none   *      none   none   1 mm oil                2 hour                                                                               yes, 1-2 mm                                                                           none   none   none   *      none   none   *                       3 hour                                                                               *      *      *      *      *      1 mm   1 mm   *                       4 hour                                                                               yes    yes, 1-2 mm                                                                           none   none   *      *      *      *                       5 hour                                                                               yes    yes    yes    yes    *      *      *      *                      __________________________________________________________________________      *Not measured.                                                           

The above expierment was preformed for evaluation of the formulation to be used as a direct feed to host animals as an insecticide. The compositions 3.I and 3.II were also diluted with soybean oil to result in 1000 ppm in AAC and did not form any ppt or separation. Thus, the formulation could be fed to the host animal (dogs) as is, or as a diluted sample in vegetable oil, e.g. soybean oil.

EXAMPLE 4

Use of N-octylpyrrolidone and N-dodecylpyrrolidone in combination.

A fourth series of experiments were carried out using the following five compositions:

                                      TABLE 4-1                                    __________________________________________________________________________                   4.1  4.2  4.3  4.4  4.5                                          __________________________________________________________________________       N-methylpyrrolidone                                                                        33.0%                                                                               33.0%                                                                               33.0%                                                                               33.0%                                                                               33.0%                                          N-octylpyrrolidone                                                                           0% 10.0%                                                                                5.0%                                                                                7.5%                                                                               15.0%                                          N-dodecylpyrrolidone                                                                       15.0%                                                                                5.0%                                                                               10.0%                                                                                7.5%                                                                                 0%                                           Aromatic petroleum                                                                         12.0%                                                                               12.0%                                                                               12.0%                                                                               12.0%                                                                               12.0%                                          oil - Exxon-200                                                                Gafac RE-610 (GAF)                                                                         14.2%                                                                               14.2%                                                                               14.2%                                                                               14.2%                                                                               14.2%                                          PRL (same as in                                                                            25.8%                                                                               25.8%                                                                               25.8%                                                                               25.8%                                                                               25.8%                                          Example 1): 92% Tech                                                                       100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                       __________________________________________________________________________

The compositions were prepared as explained in Example 1. Each of the emulsified concentrates thus prepared was analyzed for ease of emulsification and emulsion stability as explained under Example 1. Results are summaryized in Table 4-2. These formulations passed three cycles of freeze-thaw between -10° C. and 55° C.

                                      TABLE 4-2                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                   Formulation                                                                             I     II    III   IV    V                                             __________________________________________________________________________     Emulsifiable                                                                            4.1   4.2   4.3   4.4   4.5                                           concentrate used                                                               conc. of AAC                                                                            25.8% 25.8% 25.8% 25.8% 25.8%                                         water used for                                                                          WHO 342 ppm hardness                                                  dilution                                                                       dilution 1.2/48.8                                                                             1.2/48.8                                                                             1.2/48.8                                                                             1.2/48.8                                                                             1.2/48.8                                      factor                                                                         conc. of CGA in                                                                         0.6%  0.6%  0.6%  0.6%  0.6%                                          diluted sample                                                                 Bloom before                                                                            Fair  Excellent                                                                            Fair  Excellent                                                                            Excellent                                     mixing                                                                         Bloom after                                                                             Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                     20 inversions                                                                  separation after mixing and standing for:                                       1 hour  <1 mm 0     Trace 0     Trace                                          2 hour  1 mm  0     Trace 0     Trace                                          3 hour  1 mm  0     <1 mm 0     Trace                                         24 hour  2 mm  0     1 mm  0     Trace                                         __________________________________________________________________________

EXAMPLE 5

Tank Mix Compatibility

A formulation containing 16.6% of the ammomium salt of 2-[4,5-dihydro-4-methyl-4-(1-methyl ethyl)-5 OXO-1 H-imidazol-2-yl]-3 quinoline carboxylic acid, (referred to herein as SCP) in the water was prepared by dissolving an appropriate quantity of the free acid in an ammonium hydroxide solution containing a stiochiometric amount of the base. The final pH was adjusted to 7.2. It is customary to use the PRL of example 1 in conjunction with SCP in the ratio of 6:1 for better weed control. The following experiment demonstrates the compatibility of different AAC's in the composition of the invention.

Formulations 4.1, 4.2, 4.3, 4.4, and 4.5 were diluted as shown in Example 4 and summarized in Table 4-2, except that 0.5g of SCP (16.6%) was also added to the water. The effect on stability and emulsion bloom from the two AAC's present are summarized in Table 5-1.

                                      TABLE 5-1                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                   Mixed AAC's - Tank Mix Capability                                              Formulation                                                                              I     II    III  IV    V                                             __________________________________________________________________________     Emulsifiable                                                                             4.1   4.2   4.3  4.4   4.5                                           concentrate used                                                               (Example 4)                                                                    conc. of AAC                                                                             25.8% 25.8% 25.8%                                                                               25.8% 25.8%                                         (Example 1)                                                                    water used for                                                                           WHO 342 ppm hardness                                                 dilution                                                                       conc. of PRL-SCP                                                                         1.05% 1.05% 1.05%                                                                               1.05% 1.05%                                         in diluted sample                                                              conc. of PRL                                                                             1.00% 1.00% 1.00%                                                                               1.00% 1.00%                                         in diluted sample                                                              conc. of SCP                                                                             0.5%  0.5%  0.5% 0.5%  0.5%                                          in diluted sample                                                              Bloom at 0-time                                                                          Excellent                                                                            Excellent                                                                            Excellent                                                                           Excellent                                                                            Excellent                                     before mixing                                                                  Bloom after                                                                              Excellent                                                                            Excellent                                                                            Excellent                                                                           Excellent                                                                            Excellent                                     20 inversions                                                                  separation after mixing and standing for:                                       1 hour   <2 mm <2 mm <1 mm                                                                               1 mm  2 mm                                           3 hour   2 mm  4 mm  1 mm 2 mm  4 mm                                          18 hour   2 mm  4 mm  2 mm 2 mm  4 mm                                          __________________________________________________________________________

Conclusion:

Use of the two component system of the invention is advantages compared to using either component along in terms of ACC stability.

EXAMPLE 6

Tank mix compatibility was also demonstrated by making the following formulations suing PRL and a freezed-dried SCP. The following formulation was prepared as explained in Example 1.

                                      TABLE 6-1                                    __________________________________________________________________________                  6.1  6.2  6.3   6.4  6.5                                          __________________________________________________________________________       N-methylpyrrolidone                                                                       35.3%                                                                               35.3%                                                                               35.3% 35.3%                                                                               35.3%                                          N-octylpyrrolidone                                                                        16.1%                                                                               12.0%                                                                                8.0%  4.0%                                                                                 0%                                           N-dodecylpyrrolidone                                                                        0%  4.0%                                                                                8.0% 12.0%                                                                               16.0%                                          Aromatic petroleum                                                                        12.8%                                                                               12.8%                                                                               12.8% 12.8%                                                                               12.8%                                          oil - Exxon-200                                                                Gafac RE-610 (GAF)                                                                         9.2%                                                                                9.2%                                                                                9.2%  9.2%                                                                                9.2%                                          PRL: 92% Tech                                                                             23.0%                                                                               23.0%                                                                               23.0% 23.0%                                                                               23.0%                                          SCP         3.7%                                                                                3.7%                                                                                3.7%  3.7%                                                                                3.7%                                          (See Example 6A)                                                                          100.0%                                                                              100.0%                                                                              100.0%                                                                               100.0%                                                                              100.0%                                       __________________________________________________________________________

The formulations shown in Example 6, i.e., 6.1 through 6.5 were diluted and the emulsion bloom and stability was evaluated as shown earlier. The results are summarized in Table 6-2. These formulations, i.e., 6.1 through 6.5, passed three cycle of freeze-thaw at 5° C. to 55° C.

EXAMPLE 6A

16.8g of SCP 97.4% Tech. were stirred with 52 ml in ammonium hydroxide until complete solution resulted. The sample was filtered over a Whatman #4 filter under suction. The filtrate was freeze-dried at 80° C. and ≦100 milliliter vacuum for a period of 24 hours.

                                      TABLE 6-2                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                   Formulation                                                                             I     II    III   IV    V                                             __________________________________________________________________________     Emulsifiable                                                                            6.1   6.2   6.3   6.4   6.5                                           concentrate used                                                               conc. of                                                                       PRL      23.0% 23.0% 23.0% 23.0% 23.0%                                         SCP      3.7%  3.7%  3.7%  3.7%  3.7%                                          water used for                                                                          WHO 342 ppm hardness                                                  dilution                                                                       dilution 2.5/47.5                                                                             2.5/47.5                                                                             2.5/47.5                                                                             2.5/47.5                                                                             2.5/47.5                                      factor                                                                         conc. of PRL                                                                            1.15% 1.15% 1.15% 1.15% 1.15%                                         in diluted sample                                                              conc. of SCP                                                                            0.185%                                                                               0.185%                                                                               0.185%                                                                               0.185%                                                                               0.185%                                        in diluted sample                                                              Bloom upon                                                                              Good  Good  Good  Fair  Excellent                                     addition                                                                       Bloom after                                                                             Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                     20 inversions                                                                  separation                                                                              4 mm  4 mm  4 mm  4 mm  2 mm                                          before mixing                                                                  separation after mixing and standing for:                                       1 hour  4 mm  4 mm  2 mm  2 mm  2 mm                                           4 hour  4 mm  4 mm  2 mm  2 mm  3 mm                                          18 hour  4 mm  4 mm  2 mm  2 mm  3 mm                                          __________________________________________________________________________

Formulations 6.3 and 6.4 produced improved stability on dilution. The cream re-emulsified after 10 inversions and reappeared 15 minutes after the 10 inversions.

EXAMPLE 7

The following formulations 7.1 through 7.5 were prepared exactly as explained in Example 1, except that N³, N³, di-N-propyl-2,3-dinitro-6-trifuloromethyl-M-phenylenediamine (PRO) was used. These formulations passed three cycles of freeze-thaw at 5° C. t 55° C.

                                      TABLE 7-1                                    __________________________________________________________________________                  7.1  7.2  7.3   7.4  7.5                                          __________________________________________________________________________       N-methylpyrrolidone                                                                       34.7%                                                                               34.7%                                                                               34.7% 34.7%                                                                               34.7%                                          N-octylpyrrolidone                                                                        15.8%                                                                               11.8%                                                                                7.9%  4.0%                                                                                 0%                                           N-dodecylpyrrolidone                                                                        0%  4.0%                                                                                7.9% 11.8%                                                                               15.8%                                          Aromatic petroleum                                                                        12.6%                                                                               12.6%                                                                               12.6% 12.6%                                                                               12.6%                                          oil - Exxon-200                                                                Gafac RE-610 (GAF)                                                                        10.6%                                                                               10.6%                                                                               10.6% 10.6%                                                                               10.6%                                          PRO: 94.7% Tech                                                                           26.3%                                                                               26.3%                                                                               26.3% 26.3%                                                                               26.3%                                                     100.0%                                                                              100.0%                                                                              100.0%                                                                               100.0%                                                                              100.0%                                       __________________________________________________________________________

The above formulations were diluted and the emulsion characteristics were evaluated as before. The results are summarized in Table 8. The results show that the use of dodecylpyrrolidone or a mixture of 75:25 N-dodecylpyrrolidone and N-octylpyrrolidone used as the second component resulted in better emulsion stability when compared to use of N-octylpyrrolidone alone.

                                      TABLE 7-2                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                   Formulation                                                                             I     II    III   IV    V                                             __________________________________________________________________________     Emulsifiable                                                                            7.1   7.2   7.3   7.4   7.5                                           concentrate used                                                               conc. of PRO                                                                            26.3% 26.3% 26.3% 26.3% 26.3%                                         water used for                                                                          WHO 342 ppm hardness                                                  dilution                                                                       dilution factor                                                                         2.5/47.5                                                                             2.5/47.5                                                                             2.5/47.5                                                                             2.5/47.5                                                                             2.5/47.5                                      conc. of PRO in                                                                         1.31% 1.31% 1.31% 1.31% 1.31%                                         diluted sample                                                                 Bloom at 0-time                                                                         Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                     before mixing                                                                  Bloom after                                                                             Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                                                            Excellent                                     20 inversions                                                                  separation                                                                              1 mm  1 mm  Trace 0     0                                             before mixing                                                                  separation after mixing and standing for:                                      0 hour   2 mm  2 mm  0     0     0                                             1 hour   2 mm  2 mm  <1 mm Trace Trace                                         2 hour   3 mm  3 mm  1.5 mm                                                                               1 mm  1 mm                                          3 hour   3 mm  3 mm  1.5 mm                                                                               1 mm  1 mm                                          4 hour   4 mm  4 mm  2 mm  1 mm  1 mm                                          __________________________________________________________________________

EXAMPLE 8

The following formulations 8.1 through 8.16 were prepared exactly as explained in Example 1 except that a fungicide N,N'-(1,4-piperazinediyl bis (2,2,2-trichloro) ethylidend)bisforamide (TRI) was used.

                                      TABLE 8-1                                    __________________________________________________________________________                   8.1  8.2  8.3  8.4  8.5  8.6  8.7  8.8                           __________________________________________________________________________     1. N-methylpyrrolidone                                                                       42.6%                                                                               42.6%                                                                               42.6%                                                                               42.6%                                                                               42.6%                                                                               42.6%                                                                               42.6%                                                                               44.0%                         2. N-octylpyrrolidone                                                                        19.4%                                                                               19.4%                                                                                9.7%                                                                                9.7%                                                                               --   --   --   10.0%                         3. N-dodecylpyrrolidone                                                                      --   --    9.7%                                                                                9.7%                                                                               19.4%                                                                               19.4%                                                                               19.4%                                                                               10.0%                         4. Aromatic petroleum                                                                        15.5%                                                                               15.5%                                                                               15.5%                                                                               15.5%                                                                               15.5%                                                                               15.5%                                                                               15.5%                                                                               16.0%                            oil - Exxon-200                                                             5. Gafac RE-610                                                                               6.4%                                                                               --    6.4%                                                                               --    6.4%                                                                               --   --   10.0%                         6. Gafac RM-710                                                                              --    6.4%                                                                               --    6.4%                                                                               --    6.4%                                                                               --   --                            7. TRI        16.1%                                                                               16.1%                                                                               16.1%                                                                               16.1%                                                                               16.1%                                                                               16.1%                                                                               16.1%                                                                               10.0%                         8. Dodecyl benzene                                                                           --   --   --   --   --   --    6.4%                                                                               --                               sulfonic acid                                                                  Tech: 97%                                                                   9. Aromatic petroleum                                                                        --   --   --   --   --   --   --   --                               oil - Texaco-150                                                            10.                                                                               Iso octylpyrrolidone                                                                      --   --   --   --   --   --   --    6.4%                            (N-2'ethyl hexyl-                                                              pyrrolidone)                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                        __________________________________________________________________________                   8.9  8.10 8.11 8.12 8.13 8.14 8.15 8.16                          __________________________________________________________________________     1. N-methylpyrrolidone                                                                       15.0%                                                                               24.0%                                                                               24.0%                                                                               24.0%                                                                               32.0%                                                                               32.0%                                                                               32.0%                                                                               24.0%                         2. N-octylpyrrolidone                                                                        40.0%                                                                               32.0%                                                                               16.0%                                                                               --   32.0%                                                                               16.0%                                                                               --   --                            3. N-dodecylpyrrolidone                                                                      --   --   16.0%                                                                               32.0%                                                                               --   16.0%                                                                               32.0%                                                                               --                            4. Aromatic petroleum                                                                        --   24.0%                                                                               24.0%                                                                               24.0%                                                                               16.0%                                                                               16.0%                                                                               16.0%                                                                               24.0%                            oil - Exxon-200                                                             5. Gafac RE-610                                                                              --    8.0%                                                                                8.0%                                                                                8.0%                                                                                8.0%                                                                                8.0%                                                                                8.0%                                                                                8.0%                         6. Gafac RM-710                                                                               5.0%                                                                               --   --   --   --   --   --   --                            7. TRI         7.5%                                                                               12.0%                                                                               12.0%                                                                               12.0%                                                                               12.0%                                                                               12.0%                                                                               12.0%                                                                               12.0%                         8. Dodecyl benzene                                                                           --   --   --   --   --   --   --   --                               sulfonic acid                                                                  Tech: 97%                                                                   9. Aromatic petroleum                                                                        32.5%                                                                               --   --   --   --   --   --   --                               oil - Texaco-150                                                            10.                                                                               Iso octylpyrrolidone                                                                      --   --   --   --   --   --   --   32.0%                            (N-2'ethyl hexyl-                                                              pyrrolidone)                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                                                                              100.0%                        __________________________________________________________________________

The ease of emulsification and emulsion stability of the above six formulations were evaluated after dilution, as before, and the results are summarized in Table 8-2.

                                      TABLE 8-2                                    __________________________________________________________________________     EMULSION STABILITY AND BLOOM CHARACTERISTICS                                   __________________________________________________________________________     Formulation                                                                              I     II     III   IV    V      VI    VII                            __________________________________________________________________________     Emulsifiable                                                                             8.1   8.2    8.3   8.4   8.5    8.6   8.7                            concentrate used                                                               conc. of TRI                                                                             16.1% 16.1%  16.1% 16.1% 16.1%  16.1% 16.1%                          water used                                                                               WHO 342 ppm hardness                                                 for dilution                                                                   dilution factor                                                                          2.45/47.5                                                                            2.45/47.5                                                                             2.45/47.5                                                                            2.45/47.5                                                                            2.45/47.5                                                                             2.45/47.5                                                                            2.45/47.5                      conc. of TRI in                                                                          0.81% 0.81%  0.81% 0.81% 0.81%  0.81% 0.81%                          the diluted sample                                                             Bloom before                                                                             Fair-Good                                                                            Fair   Fair-Good                                                                            Fair  Fair-Good                                                                             Fair-Good                                                                            Poor                           mixing                                                                         after 20  Excellent                                                                            Excellent                                                                             Excellent                                                                            Excellent                                                                            Excellent                                                                             Excellent                                                                            Excellent                      inversions                                                                     separation                                                                               4 mm  5 mm   3 mm  5 mm  3.5 mm --    8 mm                           at 0 time                                                                      ppt/separations after mixing and standing for:                                 0 hour    0     0      0     0     0      0     0                              1 hour    2 mm  2 mm   2 mm  4 mm  2 mm   2 mm  4 mm, oil                      2 hour    2 mm  2 mm   2 mm  4 mm  2 mm   3 mm  4 mm, oil                      4 hour    4 mm  4 mm   3.5 mm                                                                               5 mm  3.5 mm 3.5 mm                               __________________________________________________________________________     Formulation                                                                             VIII IX   X    XI   XII  XIII XIV  XV   XVI                           __________________________________________________________________________     Emulsifiable                                                                            8.8  8.9  8.10 8.11 8.12 8.13 8.14 8.15 8.16                          concentrate used                                                               conc. of TRI                                                                            10%  7.5% 12%  12%  12%  12%  12%  12%  12%                           water used                                                                              WHO 342 ppm hardness                                                  for dilution                                                                   dilution factor                                                                         0.8/49.2                                                                            1.0/49                                                                              0.7/49.3                                                                            0.7/49.3                                                                            0.7/49.3                                                                            0.7/49.3                                                                            0.7/49.3                                                                            0.7/49.3                                                                            0.7/49.3                      conc. of TRI in                                                                         0.16%                                                                               0.15%                                                                               0.17%                                                                               0.17%                                                                               0.17%                                                                               0.17%                                                                               0.17%                                                                               0.17%                                                                               0.17%                         the diluted sample                                                             Bloom before                                                                            Poor Poor Fair Good Fair Fair Fair Fair Fair                          mixing                                                                         after 20 Excellent                                                             inversions                                                                     ppt/separations after mixing and standing for:                                  1 hour  --   --   Trace                                                                               Trace                                                                               0    Trace                                                                               Trace                                                                               Trace                                                                               Trace                          2 hour  Trace                                                                               0    --   --   --   --   --   --   --                             4 hour  <1 mm                                                                               0    Trace                                                                               Trace                                                                               Trace                                                                               <1 mm                                                                               <1 mm                                                                               Trace                                                                               <1 mm                         24 hour  1 mm 1 mm 1.5 mm                                                                              1 mm <1 mm                                                                               1.5 mm                                                                              1 mm 1 mm <1 mm                                       oil on top                                                       *after 24 hour settling, filtered through screens                               60 mesh +    --   --   ++   ++   +    --   --   +                             100 mesh +    --   +    +    +    +    +    --   +                             250 mesh ++   --   +    ++   ++   ++   ++   +    ++                            __________________________________________________________________________      *-- means no sediment;                                                         + means trace;                                                                 ++ means more than trace sediment but unmeasurable by weighing.          

EXAMPLE 9

The following formulation 9.1 was prepared exactly as explained in Example 1, except that N-(2'-ethylhexyl-pyrrolidone) was used in the place of N-octylpyrrolidone.

                  TABLE 9-1                                                        ______________________________________                                         Formulation and % Composition                                                                      9.1                                                        ______________________________________                                         1.         N-methylpyrrolidone                                                                           33.0%                                                2.         N-(2'-ethylhexylpyrro-                                                                        15.0%                                                           lidone)                                                             3.         Aromatic Petroleum                                                                            12.0%                                                           oil - Exxon 200                                                     4.         PRL Tech. 92% (see                                                                            26.0%                                                           Example 1)                                                          5.         Gafac RE-610 (GAF)                                                                            14.0%                                                           TOTAL          100.0%                                               ______________________________________                                    

This formulation did not freeze at 5° C. The ease of emulsificiation and stability on dilution are shown in Table 9-2.

                  TABLE 9-2                                                        ______________________________________                                         Formulation        9.1                                                         ______________________________________                                         Conc. of PRL:      26.0%                                                       Water used for dilution                                                                           WHO 342 PPM hardness                                        Dilution factor    2.5 g/47.5 g                                                Conc. of PRL in the                                                                               1.3%                                                        diluted sample                                                                 Bloom at 0 time    Excellent                                                   Bloom after 20     Excellent                                                   inversions                                                                     Separation of cream after 20                                                   inversions and on standing after:                                               1 hour            Trace                                                        3 hours           <1 mm                                                        4 hours           <1 mm                                                       24 hours           <1 mm                                                       ______________________________________                                    

After standing for 24 hours, 20 inversions and filtration through 60 mesh, 100 mesh and 2590 mesh screens, no sediment was left, even on a 250 mesh screen. 

What is claimed is:
 1. A stable emulsifiable concentrate comprising an agriculturally active herbicide which is substantially insoluble in water, an organic diluent, a surfactant and a solvent composed of first and second components, said first component having a sufficiently high hydrophilic property and being present in an amount effective to solubilize the argiculturally active herbicide, and the second component being selected from the group cnsisting of octylpyrrolidone, dodecylpyrrolidone, N-2-ethylhexylpyrrolidone, and mixtures thereof, and being present in n amount, in conuunction with a surfactant, effective to disperse the agriculturally active herbicide.
 2. A stable emulsifiable concentrate comprising an agriculturally active herbicide which is substantially insoluble in water, an aromtic petroleum oil comprising about 60% of heavy aromatic solvent naptha and about 40% of middle distillate solvent extractant having a fractional dispersive solubility parameter of greater than about 70% and a molar volume of greater than about 90 CM³ /mole, a surfactant and a solvent composed of first and second components, said first component having a sufficiently high hydrophilic property and being resent in an amount effective to solubilize the argiculturally active herbicide, and the second component being selected from the group consisting of octylpyrrolidone, dodecylpyrrolidone, N-2-ethylehxypyrrolidone, and mixtures thereof, and being present in an amount, in conjunction with a surfactant, effective to disperse the agriculturally active herbicide. 